You might have worked on this first problem before:

Use 4 four times with simple operation symbols so that the anwer 12 is arrived at.

If you get really stuck, you can press the CLUE button to see some possible answers.

Now, can you redo this so that you get 15, 16 and 17 for your answers?

Need more of a challenge? Try getting answers all the way from 0 through to 10.